A thing may or may not be happening. Speakers are allegedly being banned from universities because of views that they hold. There are certain 'extremist' groups whose representatives have been banned - fascist and racist groups like the BNP and the EDL or extreme Islamist groups associated with anti-semitism and homophobia like Al-Muhajiroun and Hizb ut-Tahrir, for instance. But there are also individual speakers, often holding controversial views on sexual matters, who have been targeted.

The clearest instance of this is that the National Union of Students in 2009 voted to ban the feminist activist Julie Bindel from its various student unions because of an article she wrote five years earlier which made a series of crass, flippant and insulting jokes about transsexuality.

This is the most explicit instance of this type of no-platforming, but earlier this year comedian Kate Smurthwaite had her invitation to Goldsmith's College withdrawn because her views on prostitution (she's against it) contravened the university's 'safe space' policy. What this seems to have meant in this case was that several people apparently planned to picket the gig and the Union would find it hard to keep the event secure.

In November 2014, a debate on abortion at Oxford University, which would have included someone offering a pro-life argument, was shut down to protect the 'students’ emotional wellbeing'.

This month Manchester's Student Union banned Julie Bindel and the horrible arsehole Milo Yiannopoulos, also for contravening its 'safe space' policy, because of the previous views expressed by these speakers.

And this week, Germaine Greer (pictured) faced a petition calling for her proposed talk at Cardiff University to be banned because of her views on trans people. A similar row broke out at Cambridge earlier this year over the same issue.

Let me say that I have always admired Germaine Greer very much but disagree strongly with her views on transwomen. I don't agree with what Julie Bindel said either (but to be fair, nor does she). I have no idea what Kate Smurthwaite's views on prostitution so I don;t know what I think about them but I do know that Milo Yiannopoulos is a horrible prick. And I'm very strongly pro-choice. For what that's worth, which isn't much.

But I also think that banning people from universities - universities, for Christ's sake - is counterproductive and the opposite of what universities should be. They should be safe spaces, yes, but safe spaces in which to hear and debate views we disagree with. It may be that some people would find the views expressed so upsetting that they would feel almost violated; then don't go. By banning these speakers, the views don't go away; it just makes them seem like martyrs.

Free speech isn't perfect. It's a horizon not a fixed position. No one believes that everyone should say whatever they are thinking at any moment. It's subtle; it's nuanced. Germaine Greer doesn't have a right to speak at Cardiff, but if she's legitimately and openly invited to speak, she should be heard by those who want to hear her. She's got decades more thinking, writing and campaigning than most of us and she's worth listening to, even if she's wrong. Because what's the worst that can happen?

Because let's say something about hate speech. Hate speech is not just mockery or disagreement. It must express and stir up hatred in the full meaning of the term. What Germaine Greer has said may offend you (it offends me a bit), but it's not hatred; it is not an act of violence; she is not whipping up people to hate or attack transwomen; she is not Hizb ut-Tahrir or the EDL; she is strongly expressing a view, however much you or I might agree.

And now, of course I don't know what it's like to be a transwoman, but I'm trying to imagine what it must be like to grow up feeling that there is something profoundly dissonant about who you are and seem to be, to realise eventually that you feel you've been born into the wrong gendered body, fighting battles within yourself over what to do, having to find incredible resources of courage to fight incredible resources of fear, finding out, probably in secret, what medical options you have, steeling yourself to tell friends, family, colleagues that you are going to transition, putting yourself through a series of arduous and physically and emotionally traumatic procedures, coping with the terrifying midwayness of transition itself, learning to adjust to a changed body, making all growing up's mistakes again, coping with the multiply complicated responses of friends and strangers. Compared to that, coping with a few crass remarks by Germaine Greer has got to be a walk in the park.

Because the only way of making these views go away is engaging with them, debating with them, showing where they are wrong. Being able to defend your own views against people who disagree is a fundamental component of having serious opinions at all. If you have to shut your eyes and cover your ears and lock your doors against your opponents, your opinions must be terribly fragile. And don't we honestly know, it's when our opinions are most fragile that we resort to closing down our opponents rather than engage with them?

And what's more, what if we're wrong? What I mean by this is: what if transwomen and women are different in some ethically/politically/cultural significant respect. Think of the politically transformative effect of 'queer' (gay people saying 'we are not just like heterosexuals') on the gay community. What if, after some time, as transexperiences become more common and everyone gets a chance to live with these new dynamics, some transpeople decide that they are not women, but something different - like, actually, the amazing Kate Bornstein has done. Are you going to tell them that they are guilty of hate speech and should not be allowed to speak in public? It is an act of monstrous historical arrogance to assume that we, in 2015, have simply got the right answers and therefore we should literally prevent anyone from challenging it. When has that ever been good? How different is that from the Inquisition showing Galileo the torture instruments to stop him arguing for a heliocentric universe?

And we shouldn't be afraid of debate. Remember when Nick Griffin went on Question Time. Lots of people were against it. I may have been nervous about it too; I honestly can't remember. But when he did go on, it put an end to the rise of the BNP. His bluster was apparent; the thinness of his ideas was obvious; he was a massively unpersuasive and unimpressive figure. Without that appearance, quite possibly, he would have continued to grow the BNP's support.

Yes, Germaine Greer and Julie Bindel and others offend you. I have probably offended someone writing this. But being offended is not a bad thing. If we try to ban being offended we are turning politics into a species of etiquette.

*****

As a postscript, let me say something else. This whole, 'no-platforming' debate has been an opportunity for the right to characterise the left as intolerant and authoritarian, wanting to restrict our freedoms from a position of holier-than-thou sanctimony. See here and here and here and here and here.

And what that does is draw attention away from the most powerful version of no-platforming in the last quarter-century. Margaret Thatcher and her followers tried to shut down a left analysis of the economy with their slogan 'There is No Alternative' (TINA). It's what Tory governments have done ever since, try to make it impossible for anyone to offer an opposing argument to their small-state, free-market, private-sector, competition-is-always-good ideology. Okay, no, it's not exactly the same thing but there are strong parallels. Note how rarely the Tories ever argue. Instead they just shut the left-wing speaker down. It's only a debate in the sense of the sixth-form common room debate, which is all bluster and ad hominem and smart-aleckisms. When have you ever heard George Osborne or David Cameron actually make a reasoned economically-literate case for austerity? Ever? They don't do it. They will not have the debate. They just smear and lie and shut down their opponents.

This most spectacularly happened in relation to the national debt; they have simply, unmistakably and wholly lied about it since 2010 and anyone who makes the - perfectly reasonable - case for public investment they smear as a 'deficit denier'. Anyone who tries to argue against welfare cuts, they ask 'where's the money going to come from' as if governments simply have no possible way to stimulate income. When Corbyn started riding high in the Labour leadership polls they said he'd 'drag us back to the eighties' (what? when the Tories were in power?); when he got elected, they insisted, without any explanation, that he would be 'a threat to our national security, our economic security and your family's security'. They pretended that he thought Osama bin Laden's death was a tragedy. They accused him of snubbing the Queen. They said he disrespected our armed forces for turning up to a Battle of Britain memorial and standing in dignified silence. There are no arguments here.

The economic arguments of the left have been 'no-platformed' since the early eighties. The reason why they are so aggressive towards Jeremy Corbyn is that here, for the first time in a generation, the debate is happening and they don't like it.

You may be here because you’ve come across a book, or play, or article of mine and you want to know more. Maybe you’re a student or a colleague or a friend or an acquaintance and you want to find out more about me. Maybe you are gathering ammunition for a vicious ad hominem attack that will expose me for the charlatan that I am.